Pixel art editor: https://github.com/Orama-Interactive/Pixelorama
Infinite canvas drawing tool: https://github.com/mbrlabs/Lorien
Trello-style kanban board: https://github.com/alfredbaudisch/Godello
Narrative designer for games: https://github.com/mhgolkar/Arrow
I tried this when Substance was aquired by Adobe. Surprisingly I found it much easier and enjoyable to use. Substance Designer feels very clumsy.
Of course Substance Designer has one unique feature, which is it's integration with Substance Painter. MM has some manual painting capabilities, but it's not a full-fledged painting app.
OpenSCAD Graph Editor is done with an earlier version and runs on Mac OS, Windows, and Linux:
Note that the Godot editor itself is written in the widget framework, so you can get a sense for how well it works just by opening Godot and clicking around.
I made a tool to position nodes in a way modelled after Cocos2D, with a position, pivot and anchor point.
I've made a series of small tools to help me lay stuff out.
One really good thing about Godot Ui is the "StyleBox" which simply allows coders to make rounded rectangles, which are so frequently used in UI it's nice to not need an artist to make a .png
Can you make some suggestions to avoid/pre-empt any said headscratchings and frustrations?
I usually recommend GDQuest on YouTube. Just start! Keep going! You'll figure it out.
XO